Phantom Bethe roots in the integrable open spin $1/2$ $XXZ$ chain

no code implementations • 5 Feb 2021 • Xin Zhang, Andreas Klümper, Vladislav Popkov

Bethe eigenstates are described by two complementary sets of Bethe Ansatz equations for regular roots, one for each invariant subspace.

Statistical Mechanics Mathematical Physics Mathematical Physics Quantum Physics

Phantom Bethe excitations and spin helix eigenstates in integrable periodic and open spin chains

no code implementations • 5 Feb 2021 • Vladislav Popkov, Xin Zhang, Andreas Klümper

The phantom Bethe roots lead to degeneracies between different magnetization sectors in the periodic case and to the appearance of spin helix states (SHS), i. e. periodically modulated states of chiral nature in both open and closed systems.

Statistical Mechanics Mathematical Physics Mathematical Physics Quantum Physics